Earplug stem



FIG. 1 is a side elevation view of an earplug stem, showing my new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a rear elevation view thereof; and,

FIG. 5 is a front elevation view thereof. 

I claim, the ornamental design for an earplug stem, as shown and described. 